Simple mosquitto subscribe implement

mosquitto.c

#include "curldefine.h"
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <mosquitto.h>
#include <string.h>

/*SUB TASK DEFINE*/
#define TOPIC "MQTT/Topic1"
#define CERT_EMQX "/tmp/tmp/broker.emqx.io-ca.crt"
#define BROKER_EMQX "broker.emqx.io"



void on_message(struct mosquitto *mosq, void *obj, const struct mosquitto_message *msg)
{
}

void on_connect(struct mosquitto *mosq, void *obj, int rc)
{
    printf("ID: %d\n", *(int *)obj);

    if (rc)
    {
        printf("TASK 3 could not connect to broker (In on_connect)! Error code: %d \n", rc);
        exit(-1);
    }
    mosquitto_subscribe(mosq, NULL, TOPIC, 0);
}
int main()
{
    int rc, id = 3;
    struct mosquitto *mosq;

    mosquitto_lib_init();

    mosq = mosquitto_new("TASK", true, &id);

    if (mosq == NULL)
    {
        fprintf(stderr, "Error: Out of memory.\n");
        return 1;
    }
    // printf("mosq pointer address: %d\n", mosq);
    if (mosq)
    {
        /*Connect and Subscribe message configure*/
        mosquitto_connect_callback_set(mosq, on_connect);
        mosquitto_message_callback_set(mosq, on_message);
        /*Openssl configure*/
        mosquitto_tls_insecure_set(mosq, true);
        mosquitto_tls_set(mosq, CERT_EMQX, NULL, NULL, NULL, NULL);
        // mosquitto_threaded_set(mosq, true);

        rc = mosquitto_connect(mosq, BROKER_EMQX, 8883, 60);
        if (rc != MOSQ_ERR_SUCCESS)
        {
            printf("go throught error fuction! \n");
            mosquitto_destroy(mosq);
            fprintf(stderr, "Error: %s\n", mosquitto_strerror(rc));
            return 1;
        }
        printf("go throught connect fuction! \n");
    }
    if (rc != MOSQ_ERR_SUCCESS)
    {
        printf("Client could not connect to broker! Error code: %d \n", rc);
        return 1;
    }

    mosquitto_loop_forever(mosq, -1, 1);

    mosquitto_disconnect(mosq);
    mosquitto_destroy(mosq);
    mosquitto_lib_cleanup();
    return 0;
}